DL-10-Camphorsulfonic acid (CAS. No- 5872-088-2) was found to be a convenient catalyst for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones through a one-pot three-component reaction of aldehydes, alkyl acetoacetate, and urea at 80°C under solvent-free conditions.
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A Simple and efficient process for tetrahydropyranylation of alcohols and phenols has been developed by reacting with dihydropyran at room temperature in presence of catalytic amount of silica supported sodium hydrogen sulphate.
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